There’s no question that engine idling has a measurable impact on a fleet’s operating costs; by some accounts, every hour of idle time can decrease fuel efficiency by 1%. For some fleets, the answer is an auxiliary power unit (APU). In comparison, an APU that provides heat, cooling and electricity can use an estimated 0.1 to 0.3 gals. of fuel per hour compared to 1 gal. or more an hour for an idling truck engine.
“Fleets can evaluate whether they can benefit from an APU by looking at their operation, including routes and the number of nights a driver uses the sleeper,” says Keith Bentz, president of Crosspoint Solutions, a subsidiary of Cummins Crosspoint that offers the ClimaCab battery-powered APU. “Today as well, hours-of-service rules and regulations that limit idling to reduce emissions and noise, as well as driver retention issues, have made cab and sleeper comfort important considerations.”
The Idle Reduction Solutions Confidence Report by the North American Council for Freight Efficiency (NACFE) details the advantages and disadvantages, functionality, driver controls, and service and maintenance issues for 19 categories of idle reduction solutions, including diesel- and battery-powered APUs. “The initial costs of APUs are higher than some other anti-idling solutions but can be offset by fuel savings, reduced engine wear, and maintenance costs,” the report states.
The report goes on to note that APUs typically weigh between 300 and 600 lbs. and with installation can cost from $8,500 to $13,000. Installation can take from five to 24 hours depending on shop expertise and the complexity of the APU design. Additionally, diesel-fired APUs require basic maintenance while battery-powered APUs need little to no maintenance, but wiring and hose connections should be checked.
The ClimaCab battery-powered APU provides 8,000 Btu/hr. of cooling in sleepers on Class 8 trucks, can be used with optional fuel-fired auxiliary heaters from Espar and Webasto, and configured to provide electrical power. Crosspoint Solutions is also working to integrate a Xantrex 1,800-watt inverter to provide power for higher hotel loads.
The Carrier Transicold APU with the same hybrid diesel-electric technology used in the Carrier Vector refrigeration unit product family provides up to 12,000 Btu/hr. of AC and 10,000 Btu/hr. of heat. Its generator delivers 6 kW of power, and the unit charges truck batteries, warms the truck engine, and is compatible with shorepower.
Thermo King’s TriPac APUs are offered in diesel and electric versions. Diesel-powered Evolution models offer 13,000 Btu/hr. of AC and up to 13,600 Btu/hr. of heat. The electric TriPac has an AC capacity of 7,200 Btu/hr. and can be specified with heating capacity up to 13,600 Btu/hr., along with an optional shorepower converter.
Other suppliers offering APUs that provide heat, AC, accessory power, battery charging and engine heat, and auxiliary heaters (some with engine heating capability) include Autotherm, Bergstrom, Dometic, Dynasys, Espar, Idle Free Systems, Pony Pack, RigMaster, Willis and Webasto. According to NACFE, several manufacturers have recently announced that they have entered into partnerships to design solar-based auxiliary power systems for trucks that will range from 30 watts for keeping batteries charged to 6,400-watt systems for electrical power.
Alternatives are on the market today as well, such as the Idle Smart automatic engine start stop solution, which monitors interior and ambient temperatures and starts and stops a vehicle to maintain desired cabin temperature. The system includes under dash and display units, a harness for ECM communication, fuel optimization software, and is transferable between vehicles.
The IdleAir Truck Stop Electrification service provides AC, heat, 120V shorepower, Internet and TV. It’s available at more than 30 Pilot Flying J, Love’s, Sapp Brothers, TravelCenters of America, and Petro locations in 15 states.
For more information, visit these websites:
Autotherm
www.autothermusa.com
Bergstrom
http://us.bergstrominc.com
Carrier Transicold
www.trucktrailer.carrier.com
Crosspoint Solutions
www.crosspointsolutionsgroup.com
Dometic
www.dometic.com/enus/Americas/USA/Truck/
Dynasys
www.dynasysapu.com
Espar
www.espar.com
IdleAir
www.IdleAir.com
Idle Free Systems
www.idlefreesystems.com
Idle Smart
www.IdleSmart.com
Pony Pack
www.ponypack.com
RigMaster Power
www.rigmasterpower.com
Thermo King
www.thermoking.com
Webasto
www.webasto.com/us
Willis Power Systems
www.willisapu.com
